When installing a terrestrial satellite antenna (TSA), the base and/or mast of the antenna must be accurately aligned relative to the horizon in order to facilitate alignment of the antenna dish mounted on the mast with an orbiting satellite. For example, when the base is mounted on the ground, it is generally preferable to align the mast perpendicular to the horizon. Similarly, if the base is mounted on a vertical structure such as a wall, it is generally preferable for the mast to be oriented parallel to the horizon. In the past, proper installation of a TSA required the services of a skilled installer utilizing a variety of leveling tools to ensure optimal mast orientation. As a result, customers and other novices were often discouraged from installing and aligning such antennas.
Moreover, after the initial installation of a TSA, its orientation may shift due to a variety of causes, such as impact with external objects, strong winds, ground settling, and the like. Therefore, realignment of the mast of a TSA is required from time to time. The novice is then faced with the choice of attempting a complicated alignment procedure, or hiring a costly installer to realign the TSA. More likely, the novice simply lets the orientation of the antenna continue to stray with ever degenerating equipment performance.
In response to the problems faced by the novice installer, several prior devices have been proposed for aiding the alignment of terrestrial satellite antennas (TSA's). For example, U.S. Pat. No. 4,495,706 to Kaminski discloses an alignment gauge which uses a pendulum and compass to indicate the azimuth and elevation angles for orienting an antenna receiving dish. U.S. Pat. No. 4,237,465 to Shibano et al. discloses a map plate having polar coordinates for use with a pendulum styled pointer to adjust the angle of elevation of an antenna dish.
U.S. Pat. No. 5,274,926 to Dillon discloses an instrument for aiming an antenna on the earth's surface toward an antenna on a satellite in geostationary orbit about the Earth. The instrument is said to include a bubble level (not shown) to align a sphere showing a map such that a line through the center of the bubble and the center of the sphere will be aimed at the center of the earth.